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comparison fuzz/fuzzer-kexdh.c @ 1756:d5680e12ac33

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Move fuzzing code to fuzz/ subdirectory, improve Makefile.in
author Matt Johnston <matt@ucc.asn.au>
date Fri, 23 Oct 2020 23:10:20 +0800
parents fuzzer-kexdh.c@a57822db3eac
children 0cc85b4a4abb
comparison
equal deleted inserted replaced
1753:7c0fcd19e492 1756:d5680e12ac33
1 #include "fuzz.h"
2 #include "session.h"
3 #include "fuzz-wrapfd.h"
4 #include "debug.h"
5 #include "runopts.h"
6 #include "algo.h"
7 #include "bignum.h"
8
9 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
10 static int once = 0;
11 static struct key_context* keep_newkeys = NULL;
12 /* number of generated parameters is limited by the timeout for the first run.
13 TODO move this to the libfuzzer initialiser function instead if the timeout
14 doesn't apply there */
15 #define NUM_PARAMS 20
16 static struct kex_dh_param *dh_params[NUM_PARAMS];
17
18 if (!once) {
19 fuzz_common_setup();
20 fuzz_svr_setup();
21
22 keep_newkeys = (struct key_context*)m_malloc(sizeof(struct key_context));
23 keep_newkeys->algo_kex = fuzz_get_algo(sshkex, "diffie-hellman-group14-sha256");
24 keep_newkeys->algo_hostkey = DROPBEAR_SIGNKEY_ECDSA_NISTP256;
25 ses.newkeys = keep_newkeys;
26
27 /* Pre-generate parameters */
28 int i;
29 for (i = 0; i < NUM_PARAMS; i++) {
30 dh_params[i] = gen_kexdh_param();
31 }
32
33 once = 1;
34 }
35
36 if (fuzz_set_input(Data, Size) == DROPBEAR_FAILURE) {
37 return 0;
38 }
39
40 m_malloc_set_epoch(1);
41
42 if (setjmp(fuzz.jmp) == 0) {
43 /* Based on recv_msg_kexdh_init()/send_msg_kexdh_reply()
44 with DROPBEAR_KEX_NORMAL_DH */
45 ses.newkeys = keep_newkeys;
46
47 /* Choose from the collection of ecdh params */
48 unsigned int e = buf_getint(fuzz.input);
49 struct kex_dh_param * dh_param = dh_params[e % NUM_PARAMS];
50
51 DEF_MP_INT(dh_e);
52 m_mp_init(&dh_e);
53 if (buf_getmpint(fuzz.input, &dh_e) != DROPBEAR_SUCCESS) {
54 dropbear_exit("Bad kex value");
55 }
56
57 ses.kexhashbuf = buf_new(KEXHASHBUF_MAX_INTS);
58 kexdh_comb_key(dh_param, &dh_e, svr_opts.hostkey);
59
60 mp_clear(ses.dh_K);
61 m_free(ses.dh_K);
62 mp_clear(&dh_e);
63
64 buf_free(ses.hash);
65 buf_free(ses.session_id);
66 /* kexhashbuf is freed in kexdh_comb_key */
67
68 m_malloc_free_epoch(1, 0);
69 } else {
70 m_malloc_free_epoch(1, 1);
71 TRACE(("dropbear_exit longjmped"))
72 /* dropbear_exit jumped here */
73 }
74
75 return 0;
76 }